U.S. patent number 10,085,453 [Application Number 15/725,073] was granted by the patent office on 2018-10-02 for controlled release, wood preserving composition with low-volatile organic content for treating in-service utility poles, posts, pilings, cross-ties and other wooden structures.
This patent grant is currently assigned to OSMOSE UTILITIES SERVICES, INC.. The grantee listed for this patent is OSMOSE UTILITIES SERVICES, INC.. Invention is credited to Douglas J. Herdman, Randy C. Marquardt, Thomas Pope, Jun Zhang.
United States Patent |
10,085,453 |
Herdman , et al. |
October 2, 2018 |
Controlled release, wood preserving composition with low-volatile
organic content for treating in-service utility poles, posts,
pilings, cross-ties and other wooden structures
Abstract
Disclosed herein are compositions including a dispersion of
solid particles of a substantially insoluble copper compound, and
an organic biocide, wherein at least 20% of all particles of the
composition have a particle size greater than 25 microns. Also
disclosed herein are methods of making and using the same.
Inventors: |
Herdman; Douglas J.
(Fayetteville, GA), Zhang; Jun (Peachtree City, GA),
Pope; Thomas (Newnan, GA), Marquardt; Randy C.
(Fayetteville, GA) |
Applicant: |
Name |
City |
State |
Country |
Type |
OSMOSE UTILITIES SERVICES, INC. |
Peachtree City |
GA |
US |
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Assignee: |
OSMOSE UTILITIES SERVICES, INC.
(Peachtree City, GA)
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Family
ID: |
54835617 |
Appl.
No.: |
15/725,073 |
Filed: |
October 4, 2017 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20180027820 A1 |
Feb 1, 2018 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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15420959 |
Jan 31, 2017 |
9808015 |
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15257632 |
Mar 14, 2017 |
9593245 |
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15062415 |
Oct 11, 2016 |
9464196 |
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14305659 |
Apr 5, 2016 |
9303169 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A01N
53/00 (20130101); C08K 3/346 (20130101); C08K
3/26 (20130101); C09D 7/44 (20180101); B27K
3/163 (20130101); A01N 59/10 (20130101); B05D
7/06 (20130101); B27K 3/32 (20130101); B27K
3/22 (20130101); A01N 43/653 (20130101); C08K
7/00 (20130101); B27K 3/12 (20130101); A01N
25/04 (20130101); C09D 101/26 (20130101); C08K
3/22 (20130101); A01N 59/20 (20130101); C09D
5/14 (20130101); B27K 3/30 (20130101); C08K
3/38 (20130101); A01N 59/14 (20130101); B27K
3/14 (20130101); B27K 2240/20 (20130101); C08K
2003/387 (20130101); B27K 3/005 (20130101); C08K
2003/2248 (20130101); B27K 3/0257 (20130101) |
Current International
Class: |
A01N
59/20 (20060101); C08K 3/38 (20060101); C08K
3/34 (20060101); C08K 3/22 (20060101); B27K
3/22 (20060101); C09D 7/00 (20180101); A01N
53/00 (20060101); A01N 59/10 (20060101); A01N
59/14 (20060101); B27K 3/32 (20060101); A01N
25/04 (20060101); A01N 43/653 (20060101); B27K
3/16 (20060101); B05D 7/06 (20060101); C09D
7/44 (20180101); B27K 3/30 (20060101); C09D
101/26 (20060101); C08K 3/26 (20060101); C08K
7/00 (20060101); C09D 5/14 (20060101); B27K
3/02 (20060101); B27K 3/14 (20060101); B27K
3/00 (20060101); B27K 3/12 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0539619 |
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May 1993 |
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EP |
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103302297 |
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Sep 2013 |
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JP |
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96/23636 |
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Aug 1996 |
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WO |
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Other References
American Wood Protection Association, Standard A3-14, "Standard
Methods for Determining Penetration of Preservatives and Fire
Retardants--Method 2--Method for Determining Penetration of
Copper-Containing Preservatives," 2014, p. 1. cited by applicant
.
American Wood Protection Association, Standard E10-12, "Standard
Method of Testing Wood Preservatives by Laboratory Soil-Block
Cultures," 2014, 11 pp. cited by applicant .
EPA Method 8260B, "Volitile Organic Compounds by Gas
Chromatography/Mass Spectrometry (GC/MS)," 1996, Revision 2. cited
by applicant .
International Search Report and Written Opinion dated Dec. 23, 2015
for related PCT Patent Application No. PCT/US15/034174. cited by
applicant .
Morrell, J.J. et al, Oregon State University--Utility Pole Research
Cooperative 33rd Annual Report, 2013, 140 pp. cited by applicant
.
Related U.S. Appl. No. 14/305,659 and the prosecution history
thereof. cited by applicant .
Related U.S. Appl. No. 15/062,415 and the prosecution history
thereof. cited by applicant .
Related U.S. Appl. No. 15/257,632 and the prosecution history
thereof. cited by applicant .
Related U.S. Appl. No. 15/420,959 and the prosecution history
thereof. cited by applicant.
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Primary Examiner: Green; Anthony J
Attorney, Agent or Firm: Troutman Sanders LLP Schutz; James
E. Simpson; Alexis N.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of and claims the
benefit of priority to U.S. patent application Ser. No. 15/420,959
(filed 31 Jan. 2017, and issued 7 Nov. 2017 as U.S. Pat. No.
9,808,015), which is a continuation of U.S. patent application Ser.
No. 15/257,632 (filed 6 Sep. 2016, and issued 14 Mar. 2017 as U.S.
Pat. No. 9,593,245), which is a continuation of U.S. patent
application Ser. No. 15/062,415 (filed 7 Mar. 2016, and issued 11
Oct. 2016 as U.S. Pat. No. 9,464,196), which is a continuation of
U.S. patent application Ser. No. 14/305,659 (filed 16 Jun. 2014,
and issued 5 Apr. 2016 as U.S. Pat. No. 9,303,169), the contents of
which are incorporated by reference herein in their entireties.
Claims
What is claimed is:
1. A composition comprising: a dispersion of solid particles of a
substantially insoluble copper compound, and an organic biocide,
wherein at least 20% of all particles of the composition have a
particle size greater than 25 microns, and wherein the dispersion
of solid particles of the substantially insoluble copper compound
is in an amount from 0.001% to 10% by weight of the
composition.
2. The composition of claim 1, wherein less than 20% of the
particles of the composition comprise particles have a particle
size greater than 100 microns.
3. The composition of claim 1, wherein the composition contains
from 1% to 5% copper atoms by weight of the composition.
4. The composition of claim 1, wherein the copper compound
comprises copper hydroxide, cupric oxide, cuprous oxide, copper
carbonate, basic copper carbonate, copper oxychloride, copper
dimethyldithiocarbamate, copper borate, or a combination
thereof.
5. The composition of claim 1, wherein the composition further
comprises a boric acid, a metal borate, a sodium borate, a
potassium borate, or a combination thereof.
6. The composition of claim 1, wherein at least 30% of the
particles of the composition have a particle size greater than 25
microns.
7. The composition of claim 1, wherein the composition contains no
more than 36 grams volatile organic compounds (VOCs) per liter of
wood preservative coating.
8. A method for remedial treatment of wood, comprising applying the
composition of claim 1 to a wooden structure.
9. The method of claim 8, wherein the wooden structure is an
in-service wood product.
10. The method of claim 8, wherein the composition is applied onto
or into the wooden structure.
11. The method of claim 8, wherein the composition is applied with
a brush.
12. The method of claim 9, wherein the in-service wood product is a
utility pole, a railroad tie, or a wooden bridge.
13. A method comprising blending particles of a substantially
insoluble copper compound; and an organic biocide; to produce a
composition, wherein at least 20% of all particles of the
composition have a particle size greater than 25 microns, wherein
the composition contains from 1% to 5% copper atoms by weight of
the composition.
14. The method of claim 13, wherein at least 30% of the particles
of the composition comprise particles have a particle size greater
than 25 microns.
15. The method of claim 13, wherein the copper compound comprises
copper hydroxide, cupric oxide, cuprous oxide, copper carbonate,
basic copper carbonate, copper oxychloride, copper
dimethyldithiocarbamate, copper borate, or a combination
thereof.
16. The method of claim 13, wherein the composition further
comprises a boric acid, a metal borate, a sodium borate, a
potassium borate, or a combination thereof.
17. The method of claim 13, wherein the substantially insoluble
copper compound is in an amount from 0.001% to 10% by weight of the
composition.
18. The method of claim 13, wherein less than 20% of the particles
of the composition comprise particles having particle size greater
than 100 microns.
19. A composition comprising: a dispersion of solid particles of a
substantially insoluble copper compound, and an organic biocide,
wherein at least 20% of all particles of the composition have a
particle size greater than 25 microns, and wherein the composition
contains no more than 36 grams volatile organic compounds (VOCs)
per liter of wood preservative coating.
20. The composition of claim 19, wherein the composition contains
from 1% to 5% copper atoms by weight of the composition.
Description
FIELD
This disclosure relates to wood preserving compositions for the
supplemental or remedial treatment of wood in service, such as
utility poles and railroad ties.
BACKGROUND
Wood and/or cellulose based products exposed in an outdoor
environment are biodegradable, primarily through attack by
microorganisms. As a result, they will decay, weaken in strength,
and discolor. The microorganisms causing wood deterioration include
brown rots such as Postia placenta, Gloeophyllum trabeum and
Coniophora puteana, white rots such as Irpex lacteus and Trametes
versicolor, dry rots such as Serpula lacrymans and Meruliporia
incrassata and soft rots such as Cephalosporium, Acremonium, and
Chaetomium. In addition, wood is still subject to attack by
wood-inhabiting insects, such as termites, beetles, ants, bees,
wasps and so on. Wood preservatives are well known for preserving
wood and extend the service life of wood products including decking
boards, fence posts, utility poles, railroad ties, permanent wood
foundation, and other cellulose-based materials, such as paper,
plywood, particleboard, textiles, rope, etc., against organisms
responsible for the deterioration of wood.
Utility poles and railroad cross ties are wooden structures that
are traditionally pressure treated with wood preservative
chemicals, such as chromated copper arsenate (CCA),
pentachlorophenol, copper naphthenate or creosote. Pressure
treatment with preserving chemicals can certainly prevent utility
poles or railroad cross ties from fungal and termite attack and the
pressure treatment can usually last for 30 to 40 years. However,
the wood preserving chemicals can only penetrate through most of
the sapwood portion of the wood species and rarely penetrate the
heartwood portion. This will cause insufficient treatment and
insufficient chemical absorption. In addition, improper treating
practices may also cause poor treatment and insufficient chemical
loadings. A direct consequence of the poor penetration and
insufficient chemical loading is that, once the treated utility
poles are placed in service, often times a small percentage of
poles show early failure and subsequent strength loss. As a result,
a supplemental or remedial treatment is needed to offer the
protection for those poles that show early failures. In older
poles, the preservative chemicals in the outer sapwood zone will
gradually decline due to water leaching, ultraviolet degradation,
chemical alteration or physical damage. As a result, external decay
or termite attack may develop on the outer surface, and therefore
there is an additional need for supplemental or remedial treatments
to further extend the service life of aging utility poles and other
wooden structures.
Preservative groundline treatments provide an economical extension
to the useful life of utility poles. Experience has shown that
groundline decay can be postponed almost indefinitely in cases
where periodic inspection and maintenance programs are in effect.
External treatments on utility poles and other wooden structures
are typically applied below the ground level either as pastes or
grease-type compositions that are brushed on the wood surface, and
then covered with a moisture resistant barrier, or as
self-contained ready-made preservative bandages. In both cases, the
goal is to supplement the original preservative treatment to
prevent or arrest surface decay. Protection is dependent upon the
ability of the active ingredients to penetrate and remain in the
treatment zone, and is limited to the depth of penetration. In
addition, the composition must possess satisfactory physical
properties, such as viscosity, spreadability, adherence, etc.
Historically, oilborne preservatives have been used for treating
in-service utility poles and other wooden structures. Traditional
oilborne preservatives included petroleum oils, creosote, copper
naphthenate and pentachlorophenol. However, the use of oilborne
supplemental preservatives is declining due to concerns of worker
exposure to the organic solvents and leaching of the organic
solvents into the environment. Furthermore, the organic solvents,
including No. 2 fuel oil, have recently experienced unprecedented
price increases making them cost prohibitive for the manufacture of
supplemental/remedial wood preservative compositions.
Current, known commercially established preservatives for the after
protection of in-service utility poles and other wooden structures
contain copper or copper combined with boron and/or fluoride as
their active biocides. Copper compounds, such as copper sulfate,
copper carbonate and copper hydroxide, are generally known to be
effective biocides as wood preservatives. Preferred copper
compounds are generally insoluble and therefore must be solubilized
to be effective in supplemental wood preservative compositions.
This is typically accomplished by complexing the copper compounds
with ammonia, acids or amines. Known copper complexes used in the
field of wood preservation include copper naphthenate,
water-dispersible copper naphthenate, copper ethanolamine,
ammoniacal copper citrate, alkaline copper quaternary and others.
Sodium fluoride and sodium borate are the most commonly used
biocides in remedial preservative compositions. The sodium salts of
boron and fluoride are able to penetrate further through the wood
structure due to their water solubility and mobility.
Although prior art compositions for the remedial treatment of
utility poles and other wooden structures have been shown to be
effective in extending the useful life of wood products in-service,
there are several problems that exist with current preservative
compositions.
One limitation of using oil or water dilutable copper complexes is
that they can readily leach from wood. Leaching of copper from wood
can be further increased by the presence of oil solvents present in
utility poles or cross ties from initial treatment with
pentachlorophenol, creosote or copper naphthenate. Elevated
moisture levels commonly found within in-service poles and ties,
particularly near or below groundline, can also increase the
leaching rate of water dilutable copper complexes found in current
preservative paste compositions.
The leaching of the copper component from current paste
compositions is a concern from both a performance and environmental
perspective. Depletion of the copper by leaching will ultimately
compromise the long term bioefficacy of the supplemental or
remedial formulation, and the leached copper causes concern that
the environment surrounding the treated structure will be
contaminated. It has been established that copper is extremely
toxic to fish and other aquatic organisms at very low
concentrations. Concerns over copper leaching from supplemental
wood preservative compositions are such that their use is often
limited or even restricted in areas of standing water or near water
ways.
The uncontrolled mobility of the copper component from current
paste compositions is a further concern from a performance
standpoint. Water soluble copper complexes provide an uncontrolled
dose to the wooden structure to be preserved by quickly dispersing
beyond the intended zone of protection within the wooden structure
and rapidly depleting the copper reservoir contained within paste
composition diminishing the ability of the treatment to provide
prolonged periods of protection from the action of decay and wood
destroying insects such as termites.
In addition, the copper component of current supplemental wood
preservative compositions is not protective against some species of
copper-tolerant wood decay fungi, often located in the Gulf-Coast
region of the U.S. Generally, higher loadings of copper are
required in remedial compositions containing soluble forms of
copper and/or a co-biocide is incorporated into the composition to
afford protection against copper-tolerant decay fungi.
Finally, complexing copper to impart solubility can be expensive.
Generally, high levels of the complexing agents are required to
solubilize copper compounds. For example, 2 to 4 moles of a
complexing or copper-solubilizing agent, such as monoethanolamine,
for example, are required to complex 1 mole of copper. In the case
of ammonia, 4 moles are required to complex 1 mole of copper. This
can add considerable cost to the formulated remedial preservative
compositions. In addition, oilborne copper naphthenate and other
oil-based compositions generally require the use of No. 2 fuel oil
as a carrier and are therefore extremely susceptible to large
variations in cost.
Examples of supplemental or remedial preservative compositions for
the afterprotection of wood in-service can be found in the
following literature.
U.S. Pat. No. 5,342,438 to West discloses a non-water dilutable
remedial wood preservative containing copper derived from an
amine-inorganic copper complex, combined with at least one sodium
salt selected from the group consisting of sodium borate and sodium
fluoride in a ratio of 2 to 120 parts of the sodium salt for each
part of copper in the preservative.
U.S. Pat. No. 6,110,263 to Goettsche teaches a process for the
afterprotection of wood, which comprises treating the wood with an
effective wood preserving amount of a wood preservative composition
comprising a copper compound, a polyamine or alkanolamine having at
least two nitrogen atoms, and an inorganic fungicide, the treatment
being effected by means of a bandaging process, an inoculation
injection process, a borehole process or a paste process.
U.S. Pat. No. 5,084,280 to West claims a paste composition for
preserving wood which contains as its only active wood preservation
ingredients a mixture of 10-90% by weight of a water-dispersible
copper naphthenate and 90-10% by weight of borax.
U.S. Pat. No. 6,352,583 to Goettsche discloses a wood preservative
for the supplemental protection of wood, consisting essentially of
one or more copper compounds, one or more alkanolmonoamines and one
or more complexing organic carboxylic acids or ammonium or alkali
metal salts of said complexing organic carboxylic acids.
U.S. Pat. No. 6,306,202 to West teaches a water soluble fixed
copper-borax wood preservative composition which comprises a fixed
copper compound selected from the group consisting of copper
oxides, copper hydroxide, basic copper carbonate, basic copper
sulfate, and copper oxychloride combined in water with sodium
tetraborate decahydrate wherein the fixed copper compound
concentration ranges from 0.01 parts to 0.20 parts for each part of
sodium tetraborate decahydrate.
U.S. Pat. No. 8,221,797 to Zhang discloses a wood preservative
composition for the supplemental or remedial treatment of
in-service poles, posts, piling, cross ties and other wooden
structures. The wood preservative composition comprises copper
8-hydroxyquinolate (oxine copper) in combination with a boron
compound or a fluoride compound wherein the copper-8-quinolinolate
is about 0.001% to about 2% by weight with a weight ratio of a
boron or fluoride compound of 1:1. The preferred form of oxine
copper in this invention is a fine particulate, such that is found
in dispersions through the milling process. Although it is not the
most preferred, the composition of this invention can also be
formulated into an oil-borne paste- or grease-like formulation
where the oxine copper is solubilized with an organic solvent.
This invention discloses a supplemental or remedial wood
preservative composition which solves the problems identified with
current, known compositions and addresses the need for a more
environmentally friendly technology for the afterprotection of
in-service wooden structures. This need is solved by the subject
matter disclosed herein.
SUMMARY
The present invention provides an aqueous wood preservative paste
composition comprising a dispersion of particles of a copper
compound; a boron-containing compound; an aqueous carrier; and a
thickening agent wherein the particles of the copper compound are
present in an amount of about 0.001% to about 10% by weight of the
composition. In one embodiment, the aqueous wood preservative paste
composition is formulated to provide a controlled release of copper
ions in a fungitoxic amount into an interior portion of the wooden
structure.
The wood preservative composition of the present invention contain
no more than about 36, 30, 20, 10, 5, 2 or 1 grams VOCs (volatile
organic compounds) per volume of the wood preservative coating. As
used herein, the unit "grams VOC per volume of the wood
preservative coating" means the mass (in grams) of VOCs per volume
of a dehydrated wood preservative composition. In contrast, the
mass VOC per volume of the wood preservative composition refers to
the mass of VOCs per volume of the wood preservative composition,
including the aqueous carrier. In one preferred embodiment, VOCs
are not detectable by gas chromatography/mass spectrometry (GC/MS),
according to EPA Method 8620, Volatile Organic Compounds by Gas
Chromatography Mass Spectrometry (GC/MS).
In one embodiment, the wood preservative composition is formulated
as a thixotropic paste.
The wood preservative paste compositions of the present invention
are preferably formulated such that at least 20, 30, 40 or 50% of
the particles of the paste composition comprise particles with
diameters greater than about 25 microns. In another embodiment, the
wood preservative compositions of the present invention are
preferably formulated such that less than 10, 15 or 20% of the
particles of the paste compositions comprise particles with
diameters below about 100 microns. Conversely, the wood
preservative compositions of the present invention are preferably
formulated such that more than 80, 85 or 90% of the particles of
the paste compositions comprise particles with diameters of about
100 microns or greater.
The wood preservative compositions of the present invention are
produced by a method comprising the step of blending solid
particles of a substantially insoluble copper compound comprising a
particle size diameter between 0.01 and 25 microns; a
boron-containing compound; an aqueous carrier; and a thickening
agent, to produce a paste composition with a viscosity of between
125 and 425 tenths of a millimeter (tmm) as measured using a
penetrometer and, in a preferred embodiment, producing a paste
composition wherein at least 20, 30, 40 or 50% of the particles of
the paste composition comprise particles with diameters greater
than about 25 microns; wherein less than 10, 15 or 20% of the
particles of the paste compositions comprise particles with
diameters below about 100 microns; or wherein more than 80, 85 or
90% of the particles of the paste compositions comprise particles
with diameters of about 100 microns or greater.
In a preferred embodiment of the present invention, the solid
particles of a substantially insoluble copper compound comprise a
particle size diameter between 0.1 and 10 microns, more preferably
between 0.1 and 5 microns and most preferably between 0.1 and 2
microns.
The present invention also provides a method of delivering a
fungitoxic amount of copper ion to an interior portion of a wooden
product comprising. These methods comprise the step of applying an
aqueous paste composition of the present invention to a wooden
structure, such as a utility pole, pole, piling, railroad tie or
other wooden structure, or the like. The application step may
comprise brushing the aqueous paste composition onto the surface of
a wooden structure or other methods of applying a remedial
treatment known in the art or described herein. In a preferred
embodiment, the interior portion of the wooden structure is an
interior region of the wooden structure extending from but
excluding the surface of the wooden structure to about 1/4 inch
from the surface of the wooden structure. In one embodiment, the
fungitoxic amount of copper ions that penetrate the wood surface
and migrate to an interior portion of a wooden structure is about
0.04 pounds per square foot (PCF). In another embodiment, the
fungitoxic amount delivered to an interior portion of a wooden
structure is not more than 5, 10, 20, 30 or 50% greater than 0.04
PCF.
The wood preservative compositions disclosed herein may also
optionally contain one or more organic biocides. In one embodiment,
the organic biocide is a fungicide, insecticide, moldicide,
bactericide, or algaecide, or combinations thereof. In a preferred
embodiment, the organic biocide is a quaternary ammonium compound,
a triazole compound, an imidazole compound, an isothiazolone
compound, or a pyrethroid compound, or combination thereof. In
another embodiment, the organic biocide is imidacloprid, fipronil,
cyfluthrin, bifenthrin, permethrin, cypermethrin, chlorpyrifos,
iodopropynyl butylcarbamate (IPBC), chlorothalonil,
2-(thiocyanatomethylthio) benzothiazole, alkoxylated diamines or
carbendazim.
In a preferred embodiment, the boron-containing compound is a boric
acid, a metal borate, a sodium borate, or a potassium borate. In
one embodiment, the sodium borate is sodium tetraborate
decahydrate, sodium tetraborate pentahydrate, or disodium
octaborate tetrahydrate (DOT). In another embodiment, the metal
borate is calcium borate, borate silicate, aluminum silicate borate
hydroxide, silicate borate hydroxide fluoride, hydroxide silicate
borate, sodium silicate borate, calcium silicate borate, aluminum
borate, boron oxide, magnesium borate, iron borate, copper borate
or zinc borate.
The present invention also provides a supplemental or remedial wood
preserving composition which comprises a copper compound combined
with at least one boron compound or fluoride compound, or
combinations thereof, which has good stability, low toxicity to
animal and plant life and high biocidal activity against wood decay
fungi and termites. The composition additionally comprises organic
fungicides and/or termiticides to further enhance the
bio-efficacy.
The present invention also provides remedial paste compositions and
methods for preservation of wooden poles, railroad ties and other
wooden structures against both fungal and termite attack and
methods of treating wooden poles, railroad ties and other wooden
structures with the wood preservative compositions of the present
invention comprising the step of either dip or brush application of
the paste compositions onto and/or into the wooden poles, railroad
ties and other wooden structures. In one embodiment, the methods
for preservation of wooden structures comprises the step of
applying the remedial paste compositions of the present invention
to cuts, holes or other injuries to previously pressure treated
wood.
The present invention provides a preventive treatment for standing
wood utility poles, piles, lumber, timber, posts, ties and other
exterior wooden structures including those standing in or in
proximity to the ground that are susceptible to attack by decay and
soft rot fungi, termites, carpenter ants, carpenter bees or wood
boring beetles.
For prevention or control of exterior infestations in utility
poles, piles, posts, and other wooden structures standing in the
ground, excavate the soil away from the structure to a depth of 18
to 24 inches. Thoroughly clean and remove any decay or damaged wood
from the treatment zone before applying the preservative. In one
embodiment, the wood preservative compositions of the present
invention are applied at rates from 1/16'' to 3/8'' thick to the
area that is about 2'' above ground line down to a depth of up to
24''. In one embodiment, the application rate and treatment zone is
dependent on the severity of condition, age and condition of the
original preservative. In another embodiment, the treatment zone,
after treatment, plus an area 2 inches above is covered with an
impermeable moisture barrier.
The invention also discloses a method for preparing a
water-dilutable supplemental or remedial wood preserving
composition which comprises either mixing, blending or milling the
insoluble copper compound in water.
The wood preservative compositions of the present invention do not
comprise one or more copper-solubilizing agents, such as ammonia,
an ammonium salt, an amine, mono- or polyalkanolamines.
The present invention also provides a method for preparing the wood
preservative composition of the present invention comprising the
step of maintaining the viscosity of the wood preservative
composition between 275 and 425 tenths of a millimeter (tmm). In a
preferred embodiment, the viscosity is maintained between 300 and
400 tmm. In a more preferred embodiment, the viscosity is
maintained between 320 and 340 tmm.The wood preservative
compositions of the present invention comprise a copper compound
that is substantially insoluble in the aqueous carrier. The copper
or copper compounds such as cuprous oxide (a source of copper (I)
ions), cupric oxide (a source of copper (II) ions), copper
hydroxide, copper carbonate, basic copper carbonate, copper
oxychloride, copper dimethyldithiocarbamate, copper omadine, copper
borate, copper residues (copper metal byproducts) or any suitable
copper source can be used. These particles exhibit a relatively low
solubility in water. In a preferred embodiment, the copper compound
is copper hydroxide, copper carbonate, or basic copper carbonate.
In one embodiment, the wood preservative composition comprises
between about 0.001% to about 10% copper atoms by weight of the
composition. In another embodiment, the wood preservative
composition comprises between about 0.01% to about 2% copper atoms
by weight of the composition. In a preferred embodiment, the wood
preservative composition comprises between about 0.1% to about 1%
copper atoms by weight of the composition. In a more preferred
embodiment, the composition contains between 1 and 5% copper atoms
by weight of the composition. In another preferred embodiment, the
composition contains between 1 and 3% copper atoms by weight of the
composition. In preferred embodiments, the wood preservative
compositions of the present invention contain between about 1 and
5%; about 1 and 3%; about 0.01 and 2% and about 0.1 and 1% copper
atoms by weight of the composition.
In preferred embodiments, the wood preservative composition of the
present invention do not comprise one or more copper-solubilizing
agents, including but not limited to ammonia, an ammonium salt, an
amine, mono- or polyalkanolamines.
The copper compounds suitable for the wood preservative
compositions of the present invention are substantially insoluble
in the aqueous carrier.
The boron-containing compound of the wood preservative compositions
of the present invention are preferably boric acid, a metal borate,
a sodium borate, or a potassium borate. In a preferred embodiment,
the sodium borate is sodium tetraborate decahydrate, sodium
tetraborate pentahydrate, or disodium octaborate tetrahydrate
(DOT). The metal borate is preferably calcium borate, borate
silicate, aluminum silicate borate hydroxide, silicate borate
hydroxide fluoride, hydroxide silicate borate, sodium silicate
borate, calcium silicate borate, aluminum borate, boron oxide,
magnesium borate, iron borate, copper borate or zinc borate. In one
embodiment, the weight ratio of the boron compound to copper--is
about 1:1. In a preferred embodiment, the weight ratio of the boron
compound to copper is about 10:1. In a more preferred embodiment,
the weight ratio of the boron compound to copper is about 25:1. In
the most preferred embodiment, the weight ratio of the boron
compound to copper is about 50:1.
The wood preservative compositions of the present invention may
further comprise a fluoride-containing compound. In one embodiment,
the fluoride compound is sodium fluoride, potassium fluoride,
calcium fluoride, copper fluoride, iron fluoride, or magnesium
fluoride. In one embodiment, the weight ratio of the fluoride
compound to copper is about 1:1. In a preferred embodiment, the
weight ratio of the fluoride compound to copper is about 10:1. In a
more preferred embodiment, the weight ratio of the fluoride
compound to copper is about 50:1. In the most preferred embodiment,
the weight ratio of the fluoride compound to copper is about 500:1.
In another embodiment, the weight ratio of the fluoride compound to
copper is between about 1:1 and about 500:1. In another embodiment,
the weight ratio of the fluoride compound to copper is between
about 1:1 and about 50:1. In yet another embodiment, the weight
ratio of the fluoride compound to copper is between about 1:1 and
about 10:1.
The wood preservative compositions of the present invention may
further comprise one or more organic biocides. The organic biocides
suitable for use with the present invention may include a
fungicide, insecticide, moldicide, bactericide, or algaecide, or
combinations thereof. In another embodiment, the organic biocide is
a quaternary ammonium compound, a triazole compound, an imidazole
compound, an isothiazolone compound, or a pyrethroid compound, or
combination thereof. In a preferred embodiment, the organic biocide
is imidacloprid, fipronil, cyfluthrin, bifenthrin, permethrin,
cypermethrin, chlorpyrifos, iodopropynyl butylcarbamate (IPBC),
chlorothalonil, 2-(thiocyanatomethylthio) benzothiazole,
alkoxylated diamines or carbendazim. In one embodiment, the weight
ratio of the organic biocide is about from 0.001% to 10% by weight.
In another embodiment, the weight ratio of the organic biocide is
about from 0.005% to 5% by weight. In yet another embodiment, the
weight ratio of the organic biocide is about from of 0.01% to 1% by
weight.
The wood preservative compositions of the present invention are
preferably formulated as pastes using an organic thickener, an
inorganic thickener or a combination of organic and inorganic
thickeners. In a preferred embodiment, the organic thickener is
cellulose-derived, such as a cellulose ester or a cellulose ether.
Preferably, the cellulose ester is cellulose nitrate, sulfate,
cellulose phosphate, cellulose nitrite, cellulose xanthate,
cellulose acetate, cellulose formate or combination thereof.
Preferably, the cellulose ether is methylcellulose, ethylcellulose,
propylcellulose, benzylcellulose, carboxymethylcellulose,
hydroxyethylcellulose, hydroxypropylcellulose,
hydroxybutylcellulose, cyanoethylcellulose, or
carboxyethylcellulose. In one embodiment, the thickening agent is
about 0.01% to 50% by weight in the composition. In another
embodiment, the thickening agent is about 0.5% to 10% by weight in
the composition.
In a preferred embodiment, the inorganic thickener of the wood
preservative compositions of the present invention is a clay.
Preferably, the clay is attapulgite, dickite, saponite,
montmorillonite, nacrite, kaolinite, anorthite, halloysite,
metahalloysite, chrysotile, lizardite, serpentine, antigorite,
beidellite, stevensite, hectonite, smecnite, nacrite, sepiolite,
montmorillonite, sauconite, stevensite, nontronite, saponite,
hectorite, vermiculite, illite, sericite,
glauconite-montmorillonite, roselite-montmorillonite, bentonite,
chlorite-vermiculite, illite-montmorillonite,
halloysite-montmorillonite, or kaolinitemontmorillonite. More
preferably, the clay is attapulgite, hectorite, bentonite,
montmorillonite, sauconite, smecnite, stevensite, beidellite,
nontronite, saponite, hectorite, vermiculite, nacrite, or
sepiolite. In one embodiment, the inorganic thickener is about 0.5%
to about 30% by weight.
The wood preservative compositions of the present invention may
also further comprise a drying retardant or a humectant, or
both.
The wood preservative composition of the present invention may be
packaged in containers, wraps, bandages and the like. In one
embodiment, the container is a can, a bucket or a bag. In one
embodiment the compositions of the present invention packaged in a
container have a viscosity between 175 and 375 tenths of a
millimeter (tmm). In a preferred embodiment, the viscosity is
between 200 and 300 tmm. In a more preferred embodiment, the
viscosity is between 210 and 250 tmm.
The present invention also provides a method for remedial treatment
of wood, comprising the step of applying the composition of the
present invention to wood. In a preferred method, the wood is an
in-service wood product, such as a utility pole, a railroad tie or
wooden bridge. Preferably, the compositions of the present
invention are applied by brush or spray. Preferably, the
composition is applied to wood to a thickness of between 1/32 and
3/4 inches. In a more preferred embodiment, the composition is
applied to wood to a thickness of between 1/16 and 1/2 inches. In a
most preferred embodiment, the composition is applied to wood to a
thickness of between 1/16 and 1/4 inches.
The boron-containing compound of the wood preservative compositions
of the present invention are preferably boric acid, a metal borate,
a sodium borate, or a potassium borate. In a preferred embodiment,
the sodium borate is sodium tetraborate decahydrate, sodium
tetraborate pentahydrate, or disodium octaborate tetrahydrate
(DOT). The metal borate is preferably calcium borate, borate
silicate, aluminum silicate borate hydroxide, silicate borate
hydroxide fluoride, hydroxide silicate borate, sodium silicate
borate, calcium silicate borate, aluminum borate, boron oxide,
magnesium borate, iron borate, copper borate or zinc borate. In one
embodiment, the weight ratio of the boron compound to copper--is
about 1:1. In a preferred embodiment, the weight ratio of the boron
compound to copper is about 10:1. In a more preferred embodiment,
the weight ratio of the boron compound to copper is about 25:1. In
the most preferred embodiment, the weight ratio of the boron
compound to copper is about 50-:1.
The wood preservative compositions of the present invention may
further comprise a fluoride-containing compound. In one embodiment,
the fluoride compound is sodium fluoride, potassium fluoride,
calcium fluoride, copper fluoride, iron fluoride, or magnesium
fluoride. In one embodiment, the weight ratio of the fluoride
compound to copper is about 1:1. In a preferred embodiment, the
weight ratio of the fluoride compound to copper is about 10:1. In a
more preferred embodiment, the weight ratio of the fluoride
compound to copper is about 50:1. In the most preferred embodiment,
the weight ratio of the fluoride compound to copper is about 500:1.
In another embodiment, the weight ratio of the fluoride compound to
copper is between about 1:1 and about 500:1. In another embodiment,
the weight ratio of the fluoride compound to copper is between
about 1:1 and about 50:1. In yet another embodiment, the weight
ratio of the fluoride compound to copper is between about 1:1 and
about 10:1.
The wood preservative compositions of the present invention may
further comprise one or more organic biocides. The organic biocides
suitable for use with the present invention may include a
fungicide, insecticide, moldicide, bactericide, or algaecide, or
combinations thereof. In another embodiment, the organic biocide is
a quaternary ammonium compound, a triazole compound, an imidazole
compound, an isothiazolone compound, or a pyrethroid compound, or
combination thereof. In a preferred embodiment, the organic biocide
is imidacloprid, fipronil, cyfluthrin, bifenthrin, permethrin,
cypermethrin, chlorpyrifos, iodopropynyl butylcarbamate (IPBC),
chlorothalonil, 2-(thiocyanatomethylthio) benzothiazole,
alkoxylated diamines or carbendazim. In one embodiment, the weight
ratio of the organic biocide is about from 0.001% to 10% by weight.
In another embodiment, the weight ratio of the organic biocide is
about from 0.005% to 5% by weight. In yet another embodiment, the
weight ratio of the organic biocide is about from of 0.01% to 1% by
weight.
The wood preservative compositions of the present invention are
prefereably formulated as pastes using an organic thickener, an
inorganic thickener or a combination of organic and inorganic
thickeners. In a preferred embodiment, the organic thickener is
cellulose-derived, such as a cellulose ester or a cellulose ether.
Preferably, the cellulose ester is cellulose nitrate, sulfate,
cellulose phosphate, cellulose nitrite, cellulose xanthate,
cellulose acetate, cellulose formate or combination thereof.
Preferably, the cellulose ether is methylcellulose, ethylcellulose,
propylcellulose, benzylcellulose, carboxymethylcellulose,
hydroxyethylcellulose, hydroxypropylcellulose,
hydroxybutylcellulose, cyano ethylcellulose, or
carboxyethylcellulose. In one embodiment, the thickening agent is
about 0.01% to 50% by weight in the composition. In another
embodiment, the thickening agent is about 0.5% to 10% by weight in
the composition.
In a preferred embodiment, the inorganic thickener of the wood
preservative compositions of the present invention is a clay.
Preferably, the clay is attapulgite, dickite, saponite,
montmorillonite, nacrite, kaolinite, anorthite, halloysite,
metahalloysite, chrysotile, lizardite, serpentine, antigorite,
beidellite, stevensite, hectonite, smecnite, nacrite, sepiolite,
montmorillonite, sauconite, stevensite, nontronite, saponite,
hectorite, vermiculite, illite, sericite,
glauconite-montmorillonite, roselite-montmorillonite, bentonite,
chlorite-vermiculite, illite-montmorillonite,
halloysite-montmorillonite, or kaolinitemontmorillonite. More
preferably, the clay is attapulgite, hectorite, bentonite,
montmorillonite, sauconite, smecnite, stevensite, beidellite,
nontronite, saponite, hectorite, vermiculite, nacrite, or
sepiolite. In one embodiment, the inorganic thickener is about 0.5%
to about 30% by weight.
The wood preservative compositions of the present invention may
also further comprise a drying retardant or a humectant, or
both.
The wood preservative composition of the present invention may be
packaged in containers, wraps, bandages and the like. In one
embodiment, the container is a can, a bucket or a bag. In one
embodiment the compositions of the present invention packaged in a
container have a viscosity between 175 and 375 tenths of a
millimeter (tmm). In a preferred embodiment, the viscosity is
between 200 and 300 tmm. In a more preferred embodiment, the
viscosity is between 210 and 250 tmm.
The present invention also provides a method for remedial treatment
of wood, comprising the step of applying the composition of the
present invention to wood. In a preferred method, the wood is an
in-service wood product, such as a utility pole, a railroad tie or
wooden bridge. Preferably, the compositions of the present
invention are applied by brush or spray. Preferably, the
composition is applied to wood to a thickness of between 1/32 and
3/4 inches. In a more preferred embodiment, the composition is
applied to wood to a thickness of between 1/16 and 1/2 inches. In a
most preferred embodiment, the composition is applied to wood to a
thickness of between 1/16 and 1/4 inches.
The present invention also provides a method for preparing the wood
preservative composition of the present invention comprising the
step of maintaining the viscosity of the wood preservative
composition between 275 and 425 tenths of a millimeter (tmm). In a
preferred embodiment, the viscosity is maintained between 300 and
400 tmm. In a more preferred embodiment, the viscosity is
maintained between 320 and 340 tmm.
DETAILED DESCRIPTION
Unless stated otherwise, such as in the examples, all amounts and
numbers used in this specification are intended to be interpreted
as modified by the term "about". Likewise, all elements or
compounds identified in this specification, unless stated
otherwise, are intended to be non-limiting and representative of
other elements or compounds generally considered by those skilled
in the art as being within the same family of elements or
compounds.
As used herein, the term "micronized" means a particle size in the
range of 0.001 to 25 microns. As used herein, the term "particle
size" means the largest axis of the particle, and in the case of a
generally spherical particle, the largest axis is the diameter.
Furthermore, it should be understood that "micronized" does not
refer only to particles which have been produced by the finely
dividing, such as by mechanical grinding, of materials which are in
bulk or other form. Micronized particles can also be formed by
other mechanical, chemical or physical methods, such as, for
example, formation in solution, with or without a seeding agent,
grinding or impinging jet. The micronized copper particles
disclosed in U.S. Patent Application Publication No. 2005/0118280
are hereby specifically incorporated by reference, in their
entirety.
As used herein, "copper-solubilizing agents" mean any agent that
promotes the solubility of copper metal or a copper compound in an
aqueous carrier. Copper-solubilizing agents include, but are not
limited to ammonia and ammonium salts, amines, and
alkanolmonoamines having between 2 to 18 carbon atoms, such as
monoalkanolmonoamines, dialkanolmonoamines, and
trialkanolmonoamines, and mixtures thereof. Examples include
monoethanolamine, diethanolamine, triethanolamine, 3-aminopropanol,
monoisopropanolamine, 4-aminobutanol, monomethylethanolamine,
dimethylethanolamine, triethylethanolamine, monoethylethanolamine,
N-methyldiethanolamine and mixtures thereof.
Disclosed herein is a supplemental/remedial composition for wood
and a method for use thereof in treatment of in-service wooden
products, more particularly utility poles, railroad ties, wooden
bridges. The composition comprises copper with a boron compound or
fluoride compound. The composition imparts to the treated wood
resistance to both fungi and insects. The composition can
additionally comprise an organic fungicide/termiticide.
In an effort to limit the level of volatile organic compounds
(VOCs) being released into the atmosphere and to minimize worker
exposure, the Environmental Protection Agency (EPA) published the
architectural coatings rule on 1988 under authority of the Clean
Air Act. The purpose of this rulemaking was to reduce the VOCs
emitted from architectural and industrial maintenance coatings thus
limiting the amount of VOCs that manufacturers can put in their
products. Remedial preservative paste formulations are defined by
EPA as architectural coatings and below ground wood preservatives.
The VOC limit established by EPA for below ground wood
preservatives is 550 grams of VOC per liter of coating. Individual
States such as Pennsylvania, New York and California (South Coast
Air Quality Management District) have established a more stringent
allowable VOC limit for below ground wood preservatives of 350
grams per liter of coating. The present invention provides
compositions containing no more than 36, 30, 20, 10, 5, 2 or 1
grams volatile organic compounds (VOCs) per liter of the
composition. In a preferred embodiment, VOCs are not detectable by
gas chromatography/mass spectrometry (GC/MS). In another preferred
embodiment, VOCs are not detectable by gas chromatography according
to EPA Method 8620, Volatile Organic Compounds by Gas
Chromatography Mass Spectrometry (GC/MS), which is incorporated
herein by reference in its entirety.
The compositions of the present invention have a broad spectrum of
bio-efficacy against wood decay fungi, including, brown rot fungi,
white rot fungi, and soft rot fungi. Non-limiting examples of brown
rot fungi include: Coniophora puteana, Serpula lacrymans, Antrodia
vaillantii, Gloeophyllum trabeum, Gleoeophyllum epiarium, Lentinum
lepideus, Oligoporus placenta, Meruliporia incrassate, Daedalea
quercina, Postia placenta. Non-limiting examples of white rot fungi
include: Trametes versicolor, Phanerochaete chrysosporium,
Pleurotus ostreatus, Schizophyllum commune, Irpex lacteus. Some
non-limited examples of soft rot fungi are Chaetomium globosum,
Lecythophora hoffmannii, Monodictys putredinis, Humicola
alopallonella, Cephalosporium, Acremonium, and Chaetomium.
The compositions of the present invention are also effective
against a broad range of insects and marine borer, including
termites, beetles, and wood-boring insects. Non-limiting examples
of termites include drywood termites such as Cryptotermes and
Kaloterms, and dampwood termites such as Zootermopsis, subterranean
termites such as Coptotermes, Mastotermes, Reticulitermes,
Schedorhinotermes, Microcerotermes, Microtermes, and Nasutitermes.
Non-limiting examples of beetles include those in families such as,
for example, Anoniidae, Bostrychidae, Cerambycidae, Scolytidae,
Curculionidae, Lymexylonidae, and Buprestidae.
The compositions of the present invention can be formulated into a
waterborne paste- or grease-type of formulation, if desired, such
that the formulation has an adhesive nature and is easy to apply to
a desired location.
The present invention includes copper. The preferred form of copper
for preparation of the aqueous paste compositions of the present
invention is a fine particulate, such that is found in dispersions
through a milling process or the like. Methods for preparing milled
substantially insoluble biocidal particulates that can be used in
aqueous wood preservative compositions that can be applied to a
wood product by vacuum and/or pressure treatment to effectively
penetrate and preserve wood may be found in U.S. Patent Application
Publication Nos. 2004/0258767, 2005/0118280 and 2006/0288904 to
Leach and Zhang. The weight ratio of copper in the composition
varies from about 0.001% to about 10% by weight. The preferred
range of weight ratio of copper in the composition varies from
about 0.1% to about 1% by weight.
The present invention also comprises a boron compound, a fluoride
compound or both. The boron compound can be either water soluble or
water insoluble. Non-limiting examples of water soluble boron
compounds include boric acid, sodium borates, such as sodium
tetraborate decahydrate, sodium tetraborate pentahydrate, and
disodium octaborate tetrahydrate (DOT) and potassium borates.
Non-limiting examples of water insoluble boron compounds include
metal borate compounds such as calcium borate, borate silicate,
aluminum silicate borate hydroxide, silicate borate hydroxide
fluoride, hydroxide silicate borate, sodium silicate borate,
calcium silicate borate, aluminum borate, boron oxide, magnesium
borate, iron borate, copper borate and zinc borate.
Preferred boron compounds are water soluble boron compounds, such
as boric acid and sodium tetraborate decahydrate, sodium
tetraborate pentahydrate and disodium octaborate tetrahydrate
(DOT).
The weight ratio of boron compound to copper can be in the range of
from about 1:1 to about 500:1, the preferred weight ratio range is
about 10:1 to about 200:1.
The present invention can also include a fluoride compound.
Non-limiting examples of fluoride compounds include sodium
fluoride, potassium fluoride, calcium fluoride, copper fluoride,
iron fluoride, magnesium fluoride, and other metal compounds of
fluoride. The preferred fluorides are sodium fluoride and potassium
fluoride. The weight ratio of fluoride compound to copper can be in
the range of from about 1:1 to about 1000:1, the preferred weight
ratio range is about 10:1 to about 200:1.
The present composition optionally comprises one or more
combinations of a organic biocides, such as quaternary ammonium
compounds, triazole or imidazole compounds, isothiazolone
compounds, pyrethroid compounds and other biocides such as
imidacloprid; fipronil; cyfluthrin; bifenthrin; permethrin;
cypermethrin; and chlorpyrifos, iodopropynyl butylcarbamate (IPBC);
chlorothalonil; 2-(thiocyanatomethylthio) benzothiazole;
alkoxylated diamines and carbendazim. When the organic biocide is
used in the composition, the weight ratio of the organic biocide in
the composition is generally in the range of from 0.001% to 10% by
weight, with a preferred range of 0.005% to 5% by weight and a more
preferred range of 0.01% to 1%.
Each of the organic biocides listed in Tables 1-4 of U.S. Patent
Application Publication No. 2005/0118280 are hereby specifically
incorporated by reference, in their entirety.
Non-limiting examples of quaternary ammonium compounds are:
didecyldimethylammonium chloride; didecyldimethylammonium
carbonate/bicarbonate; alkyldimethylbenzylammonium chloride;
alkyldimethylbenzylammonium carbonate/bicarbonate;
didodecyldimethylammonium chloride; didodecyldimethylammonium
carbonate/bicarbonate; didodecyldimethylammonium propionate;
N,N-didecyl-N-methyl-poly(oxyethyl)ammonium propionate.
Non-limiting examples of triazole or imidazole compounds are:
14[242,4-dichlorophenyl)-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole(azac-
onazole), 1-R2RS,4RS:2RS,
4SR)-4-bromo-2-(2,4-dichlorophenyptetrahydrofurfuryl]-1H-1,2,4-triazole(b-
romuconazole),
2RS,3RS;2RS,3SR)-2-(4-chlorophenyl)-3-cyclopropyl-1-(1H-1,2,4-triazol-1-y-
l)butan-2-ol(Cyproconazole),
(2RS,3RS)-1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pe-
ntan-3-ol(diclobutrazol),
cis-trans-3-chloro-444-methyl-2-(1H-1,2,4-triazol-1-ylmethyl)-1,3-dioxola-
n-2-yliphenyl 4-chlorophenyl ether(difenoconazole),
(E)-(R5)-1-(2,4-dichloro-phenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pe-
nt-1-en-3-ol(diniconazole),
(E)-.RTM.-1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pe-
nt-1-en-3-ol(diniconazole-M),
(2RS,3SR)-143-(2-chlorophenyl)-2,3-epoxy-2-(4-fluorophenyl)propyl]-1H-1,2-
,4-triazole(epoxycon-azole),
(RS)-142-(2,4-dichlorophenyl)-4-ethyl-1,3-dioxolan-2-ylmethyli-1H-1,2,4-t-
riazole(etaconazole),
(RS)-4-(4-chlorophenyl)-2-phenyl-2-(1H-1,2,4-triazol-1-ylmethyl)butyronit-
rile(fenbuconazole),
3-(2,4-dichlorophenyl)-6-fluoro-2-(1H-1,2,4-triazol-1-yl)quinazolin-4(311-
)-one(fluquinconazole),
bis(4-fluorophenyl)(methyl)(1H-1,2,4-triazol-1-ylmethyl)silane(flusilazol-
e), (RS)-2,4'-difluoro-a-(1H-1,2,4-triazol-1-ylmethyl)benzhydryl
alcohol(flutriafol), (2RS, 5RS; 2RS,
5SR)-5-(2,4-dichlorophenyl)19arboxymet o-5-(1
H-1,2,4-triazol-1-ylmethyl)-2-furyl 2,2,2-trifluoroethyl
ether(furconazole), (2RS,5RS)-5-(2,4-dichlorophenyptetrahydro-54 1
H-1,2,4-triazol-1-ylmethyl)-2-furyl 2,2,2-trifluoroethyl
ether(furconazole-cis),
(RS)-2-(2,4-dichlorophenyl)-1-(1H-1,2,4-triazol-1-yl)hexan-2-ol(hexaconaz-
ole), 4-chlorobenzyl (EZ)-N-(2,4-dichlorophenyl)-2-(1
H-1,2,4-triazol-1-yl)thioacetamidate(imibenconazole), (1RS,2SR,5RS;
1RS,2SR,5SR)-2-(4-chlorobenzyl)-5-isopropyl-1-(1
H-1,2,4-triazol-1-ylmethyl)cyclopentanol (ipconazole), (1RS,5RS;
1RS,5SR)-5-(4-chlorobenzyl)-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmethyl)c-
yclopentanol (metconazole), (RS)-2-(4-chlorophenyl)-24
1H-1,2,4-triazol-1-ylmethyl)hexanenitrile (myclobutanil),
(RS)-1-(2,4-dichloro-(3-propylphenethyl)-1H-1,2,4-triazole(penconazole),
cis-trans-1-[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-ylmeth-yl]-1H-
-1,2,4-triazole(propiconazole),
(RS)-2-[2-(1-chlorocyclopropyl)-3-(2-chlorophenyl)-2-hydroxypropyl
1-2,4-dihydro-1,2,4-triazole-3-thione(prothioconazole),
3-(2,4-dichlorophenyl)-2-(1H-1,2,4-triazol-1-yl)-quinazolin-4(311)-one(qu-
inconazole),
(RS)-2-(4-fluoro-phenyl)-1-(1H-1,2,4-triazol-1-yl)-3-(trimethylsilyl)prop-
an-2-ol(simeconazole),
(RS)-1-p-chlorophenyl-4,4-dimethyl-3-(1H-1,2,4-triazol-1-ylmethyl)pentan--
3-ol(tebuconazole), propiconazole,
(RS)-2-(2,4-dichlorophenyl)-3-(1H-1,2,4-triazol-1-yl)propyl
1,1,2,2-tetrafluoroethyl ether(tetracon-azole),
(RS)-1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-on-
e(triadime-fon), (1RS,2RS;
1RS,2SR)-1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butan--
2-ol(triadimenol),
(RS)-(E)-5-(4-chlorobenzylidene)-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmet-
hyl)cyclopentanol(triticonazole),
(E)-(RS)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pent-1--
en-3-ol (uniconazole),
(E)-(S)-1-(4-chlorophenyl)-4,4-dimethyl-241H-1,2,4-triazol-1-yl)pent-1-en-
-3-ol(uniconazole-P), and
2-(2,4-difluorophenyl)-1-(1H-1,2,4-triazole-1-yl)-3-trimethylsilyl-2-prop-
anol. Other azole compounds include: amisulbrom, bitertanol,
fluotrimazole, triazbutil, climbazole, clotrimazole, imazalil,
oxpoconazole, prochloraz, triflumizole, azaconazole, simeconazole,
and hexaconazole.
Non-limiting examples of isothiazolone compounds are:
methylisothiazolinone; 5-chloro2-methyl-4-isothiazoline-3-one,
2-methyl-4-isothiazoline-3-one, 2-n-octyl-4-isothiazoline-3-one,
4,5-dichloro-2-n-octyl-4-isothiazoline-3-one,
2-ethyl-4-isothiazoline-3-one,
4,5-di-chloro-2-cyclohexyl-4-isothiazoline-3-one,
5-chloro-2-ethyl-4-isothiazoline-3-one, 2-octyl-3-isothiazolone,
5-chloro-2-t-octyl-4-isothiazoline-3-one,
1,2-benzisothiazoline-3-one, preferably
5-chloro-2-methyl-4-isothiazoline-3-one,
2-methyl-4-isothiazoline-3-one, 2-n-octyl-4-isothia-zoline-3-one,
4,5-dichloro-2-n-octyl-4-isothiazoline-3-one,
1,2-benzisothiazoline-3-one, etc., more preferably
5-chloro-2-methyl-4-isothiazoline-3-one,
2-n-octyl-4-isothiazoline-3-one,
4,5-dichloro-2-n-octyl-4-isothiazoline-3-one,
1,2-benzisothiazoline-3-one, chloromethylisothi-azolinone;
4,5-Dichloro-2-n-octyl-3(2H)-isothiazolone;
1,2-benziothiazolin3-one.
Non-limiting examples of pyrethroid compounds include acrinathrin,
allethrin, bioallethrin, barthrin, bifenthrin, bioethanomethrin,
cyclethrin, cycloprothrin, cyfluthrin, betacyfluthrin, cyhalothrin,
gamma-cyhalothrin, lambda-cyhalothrin, cypermethrin,
alphacypermethrin, beta-cypermethrin, theta-cypermethrin,
zeta-cypermethrin, cyphenothrin, deltamethrin, dimefluthrin,
dimethrin, empenthrin, fenfluthrin, fenpirithrin, fenpropathrin,
fenvalerate, esfenvalerate, flucythrinate, fluvalinate,
tau-fluvalinate, furethrin, imiprothrin, metofluthrin, permethrin,
biopermethrin, transpermethrin, phenothrin, prallethrin,
profluthrin, pyresmethrin, resmethrin, bioresmethrin, cismethrin,
tefluthrin, terallethrin, tetramethrin, tralomethrin,
transfluthrin, etofenprox, flufenprox, halfenprox, protrifenbute,
silafluofen.
Preferred organic biocides are tebuconazole and bifenthrin.
The present invention also optionally comprises an aqueous type
thickening agent. Aqueous organic polymer, aqueous emulsion, clay
minerals, phosphate and the like are the aqueous type of thickening
agents. Typical examples of aqueous organic polymers are cellulose
derivatives including cellulose esters and ethers. Examples of
cellulose esters are cellulose nitrate, sulfate, cellulose
phosphate, cellulose nitrite, cellulose xanthate, cellulose
acetate, cellulose formate, and cellulose esters with other organic
acids. Examples of cellulose ethers are methylcellulose,
ethylcellulose, propyl cellulose, benzyl cellulose,
carboxymethylcellulose, hydroxyethylcellulose,
hydroxypropylcellulose, hydroxybutylcellulose, cyanoethyl
cellulose, and 21 arboxymethylcellulose. The preferred cellulose
derivatives are cellulose ethers such as hydroxyethylcellulose,
hydroxypropyl cellulose, carboxymethylcellulose and
carboxyethyl-cellulose. The weight percentage of the cellulose
derivative in the paste formulation is generally in the range of
from about 0.01% to 50% with a preferred weight percentage of 0.1%
to 20% and a more preferred weight percentage of 0.5% to 10%.
Furthermore, the present invention also optionally comprises about
0.5% to about 30% of an inorganic clay thickening agent, or a
mixture of such thickening agents. The inorganic clay thickening
agents include a fibrous structure type such as attapulgite clay
and sepiolite clay, a non-crystal structure type such as allophone,
and mixed layer structure type such as montmorillonite and kaolinte
and the above layer structure types. Examples of inorganic clay
minerals, but not limited to, are: attapulgite, dickite, saponite,
montmorillonite, nacrite, kaolinite, anorthite, halloysite,
metahalloysite, chrysotile, lizardite, serpentine, antigorite,
beidellite,stevensite, hectonite, smecnite, nacrite and sepiolite,
montmorillonite, sauconite, stevensite, nontronite, saponite,
hectorite, vermiculite, smecnite, sepiolite, nacrite, illite,
sericite, glauconite-montmorillonite, roselite-montmorillonite,
Bentone 38 (hectorite) and Bentone 34 (bentonite),
chlorite-vermiculite, illite-montmorillonite,
halloysite-montmorillonite, kaolin-itemontmorillonite. The clay
minerals employed in the compositions of the present invention also
contain exchangeable cations including, but not limited to,
aluminum ions, protons, sodium ions, potassium ions, calcium ions,
magnesium ions, lithium ions, and the like.
Among the above inorganic clay minerals, attapulgite, hectorite,
bentonite, montmorillonite, sauconite, smecnite, stevensite,
beidellite, nontronite, saponite, hectorite, vermiculite, nacrite,
and sepiolite are particularly preferable for the present
invention.
Further, these inorganic clay minerals show a good thickening
effect and thixotopic property in comparison with other aqueous
thickening agents. Therefore, they show a little sagging and also
they are very easy to be rinsed out by water in comparison with
organic thickening agents.
It should be appreciated that thickening agents other than
described herein can be used.
Optionally, the present invention also includes chemical additives
that retard the drying of the paste composition. These are usually
a blend of several glycols, such as ethylene glycol, propylene
glycol, polyethylene glycol, polypropylene glycol and their
derivatives. By evaporating far more slowly than water, glycols or
their derivatives can slow down the drying process of the paste
composition. Humectants, such as glycerin and glycerol that absorb
or hold water can also be added to retard or slow drying.
The preservative paste compositions of this invention can be
applied by various processes of supplemental or remedial treatment
or protection of in-service wooden structures. The compositions of
this invention are suitable for incorporation into wraps or
ready-to-use bandages, injection into voids or cavities by pressure
or by gravity and solid rods or cartridges.
The paste compositions of this invention can be easily incorporated
into a suitable support material to form a ready-to-use bandage or
wrap that can applied to in-service utility poles and other wooden
structures. Numerous support materials have been identified in
literature and may include polymer films, fabrics, fiberglass,
polyester fiber, polypropylene, porous polymer compositions and
others that allow for the transfer or diffusion of preservative
chemical from the bandage to the wood substrate. The paste
composition may be applied to the support material by toweling,
rolling, brushing and the like. The paste composition can be
directly applied to the support material or may require the use of
a binder or resin such as for example acrylate resins or PVC with
plasticizers. To improve the adhesion between the paste
compositions and support material the combination may be air-dried
or dried in an oven at elevated temperatures.
The paste compositions of this invention may also be formed into
solid rods by extrusion, rolling or pressing. Once sufficiently
dried, the rods can be cut to length and inserted into predrilled
holes in in-service utility poles or other wooden structures. As
with the bandages or wraps, resins or binders may be added to
improve the dimensional stability of the rods.
The paste compositions of this invention may be injected into
internal voids or cavities through predrilled holes into in-service
poles, posts, piling, cross-ties and other wooden structures by
pressure processes or by gravity feed.
The following examples are provided to further describe certain
embodiments of the invention, their preparation and application as
remedial or supplemental paste preserving system, but are in no way
meant to limit the scope of the invention. For the experiments,
penetration testing has been found to be an effective means of
establishing the consistency and shear stability of compositions of
this invention. Penetrometers are generally used for consistency
tests on a wide range of food products, cosmetics, greases, pastes
and other solid to semisolid products. Penetrometers utilize a
standard cone or needle that is released from the Penetrometer and
allowed to drop feely into the sample for 5 seconds at constant
temperature. The depth of penetration of the cone into the sample
is measured in tenths of a millimeter (tmm) by the Penetrometer. It
has been established through testing that the preferable
penetration of the compositions of this invention range from about
125 to 425 tmm when using a standard Penetrometer equipped with a
102.5 gram brass cone with a stainless steel tip. A more preferable
range of consistency for the present invention is about 175 to 375
tmm and a consistency or shear stability of about 200 to 300 tmm is
particularly preferable for the present invention.
The preferred viscosities of the thixotropic compositions of the
present invention, during manufacture, is between 275 and 425
tenths of a millimeter (tmm) viscosity as measured using a
penetrometer. More preferably the viscosities of the compositions
of the present invention is between 300 and 400 tmm. Most
preferably the viscosities of the compositions of the present
invention is between 320 and 340 tmm.
The preferred viscosities of the thixotropic compositions of the
present invention is between 175 and 375 tenths of a millimeter
(tmm) viscosity as measured using a penetrometer. More preferably
the viscosities of the compositions of the present invention is
between 200 and 300 tmm. Most preferably the viscosities of the
compositions of the present invention is between 210 and 250
tmm.
For determination of acceptability of viscosity, spreadability and
adherence, compositions of the present invention can be rolled,
troweled or brushed on wooden objects or more preferably to
in-service utility poles, cross-ties or other wooden structures.
Desirable compositions of the present invention should be
self-supporting, have good spreadability such that the composition
can be easily applied with a roller, trowel or brush without
running or slumping off the wooden substrate or application tool
and will easily adhere to a wooden substrate.
EXAMPLES
The Examples listed below illustrate methods for preparing various
compositions and treating wood according to the invention. These
Examples below, illustrate methods for preparing alternative
versions of the inventive compositions. The methods described in
these Examples are illustrative only, and are not intended to limit
the invention in any manner and should not be construed to limit
the scope of claims herein.
Example 1
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 41.60 parts water, 6.00
parts of a fine copper dispersion comprised of 33.3% copper
carbonate, 0.50 parts of a commercially available cellulose ether
thickener, 43.70 parts sodium tetraborate decahydrate, and 8.20
parts attapulgite clay thickener. This remedial preservative paste
contained 2.00 parts copper as derived from the fine copper
carbonate dispersion for a weight ratio of 21.90 parts boron
compound to 1.00 part copper.
The supplemental/remedial preservative paste composition formulated
according to the above example was applied to a wooden substrate
using a trowel and was found to have desirable physical properties
including viscosity, spreadability and adherence for application to
in-service utility poles, cross-ties and other wooden structures.
Consequently, a preservative paste composition was obtained.
Example 2
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 33.30 parts water, 3.00
parts of a fine copper dispersion comprised of 33.3% copper
hydroxide, 10.00 parts glycerin, 2.00 parts of a commercially
available cellulose ether thickener, 43.70 parts sodium tetraborate
decahydrate, 1.00 part calcium sulfate filler and 7.00 parts
attapulgite clay thickener. This remedial preservative paste
contained 1.00 parts copper as derived from the fine copper
hydroxide dispersion for a weight ratio of 43.70 parts boron
compound to 1.00 part copper.
The supplemental/remedial preservative paste composition formulated
according to the above example was applied to a wooden substrate
using a trowel and was found to have desirable physical properties
including viscosity, spreadability and adherence for application to
in-service utility poles, cross-ties and other wooden structures.
Consequently, a preservative paste composition was obtained.
Example 3
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 30.24 parts water, 1.50
parts of a fine copper dispersion comprised of 33.3% basic copper
carbonate, 10.00 parts glycerin, 3.00 parts of a commercially
available cellulose ether thickener, 47.76 parts sodium tetraborate
decahydrate, 1.50 part calcium sulfate filler and 6.00 parts
attapulgite clay thickener. This remedial preservative paste
contained 0.50 parts copper as derived from the fine basic copper
carbonate dispersion for a weight ratio of 95.52 parts boron
compound to 1.00 part copper.
The supplemental/remedial preservative paste composition formulated
according to the above example was applied to a wooden substrate
using a trowel and was found to have desirable physical properties
including viscosity, spreadability and adherence for application to
in-service utility poles, cross-ties and other wooden structures.
Consequently, a preservative paste composition was obtained.
Example 4
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 44.60 parts water, 0.02
parts bifenthrin, 3.00 parts of a fine copper dispersion comprised
of 33.3% cupric oxide, 0.50 parts of a commercially available
cellulose ether thickener, 43.70 parts sodium tetraborate
decahydrate, and 8.2 parts attapulgite clay thickener. This
remedial preservative paste contained 1.00 parts copper as derived
from the fine cupric oxide dispersion for a weight ratio of 43.7
parts boron compound to 1.00 part copper.
Example 5
A supplemental/remedial preservative paste composition is prepared
by blending together in the order listed; 34.00 parts water, 0.10
parts tebuconazole, 2.25 parts of a fine copper dispersion
comprised of 33.3% basic copper carbonate, 10.00 parts glycerin,
3.00 parts of a commercially available cellulose ether thickener,
21.85 parts sodium tetraborate decahydrate, 21.85 parts boric acid,
1.00 part calcium sulfate filler and 6.0 parts attapulgite clay
thickener.
This remedial preservative paste contains 0.75 parts copper as
derived from the fine basic copper carbonate dispersion for a
weight ratio of 58.27 parts boron compound to 1.00 part copper.
Example 6
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 44.6 parts water, 0.50
parts of a commercially available cellulose ether thickener, 3.00
parts of a fine copper hydroxide dispersion comprised of 33.3%
copper carbonate, 0.10 parts bifenthrin, 0.10 parts tebuconazole,
43.70 parts sodium tetraborate decahydrate, 6.5 parts attapulgite
clay thickener and 1.5 parts calcium sulfate filler. This remedial
preservative paste contained 1.00 parts copper as derived from the
fine copper carbonate dispersion for a weight ratio of 43.7 parts
boron compound to 1.00 part copper.
Penetration testing performed on the paste composition formulated
according to the example above showed a penetration of 216 tmm. In
addition, the supplemental/remedial preservative paste composition
formulated according to the above example was applied to a wooden
substrate using a trowel and was found to have desirable physical
properties including viscosity, spreadability and adherence for
application to in-service utility poles, cross-ties and other
wooden structures. Consequently, a preservative paste composition
was obtained.
Example 7
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 37.00 parts water, 6.51
parts of a fine copper dispersion comprised of 31.6% cuprous oxide,
0.50 parts of a commercially available cellulose ether thickener,
50.00 parts sodium tetraborate decahydrate, and 6.00 parts
attapulgite clay thickener. This remedial preservative paste
contained 2.06 parts copper as derived from the fine cuprous oxide
dispersion for a weight ratio of 24.27 parts boron compound to 1.00
part copper.
Penetration testing performed on the paste composition formulated
according to the example above showed a penetration of 275 tmm.
Further, the paste composition formulated according to the above
example was brushed to 18 inches of the below ground section of an
in-service utility pole. This paste was found to have desirable
physical properties including viscosity, spreadability and
adherence for application to in-service utility poles, cross-ties
and other wooden structures. Consequently, a preservative paste
composition was obtained.
Example 8
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 44.6 parts water, 3.00
parts of a fine copper dispersion comprised of 33.3% copper
carbonate, 0.70 parts pigmented dyes, 0.50 parts of a commercially
available cellulose ether thickener, 43.70 parts sodium tetraborate
decahydrate, and 7.50 parts attapulgite clay thickener. This
remedial preservative paste contained 1.0 parts copper as derived
from the fine copper carbonate dispersion for a weight ratio of
43.7 parts boron compound to 1.00 part copper.
Penetration testing performed on the paste composition formulated
according to the example above showed a penetration of 211 tmm.
Further, the paste composition formulated according to the above
example was brushed to 18 inches of the below ground section of an
in-service utility pole by an experienced preservative chemical
applicator. This paste was found to have desirable physical
properties including viscosity, spreadability and adherence for
application to in-service utility poles, cross-ties and other
wooden structures. Consequently, a preservative paste composition
was obtained.
Further, the paste formed was applied to the surface of southern
pine dimensional lumber that had previously been vacuum-pressure
impregnated with water. The lumber was saturated with water to
simulate moisture regimes that are typically present within the
ground-line region of in-service utility poles and other wooden
structures and that is required to provide mobility of the
preservative paste into the wood substrate. The paste was applied
at a thickness of a sixteenth of an inch and sealed to the lumber
with a water impermeable wrap such that is used in commercial
practice. At periods of 2, 4 and 6 weeks, small incremental wafers
were taken from the treated sections of the lumber. Wafers were
sprayed with the copper penetration reagent Chrome Azurol S in
accordance with American Wood Protection Association's (AWPA)
Standard A3-08 (which is incorporated herein by reference in its
entirety), Method 2, Method for Determining Penetration of
Copper-Containing Preservatives. It was determined by visual
inspection that copper had penetrated, or diffused through the wood
up to a 1/4 inch from the surface of application. It was further
visually determined that boron had penetrated the wood up to 1-1/2
inches from the treated surface using AWPA Standard A3-08, Method
17, Standard Method for Determining Penetration of Boron-Containing
Preservatives and Fire Retardants.
Example 9
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 45.05 parts water, 3.00
parts of a fine copper dispersion comprised of 33.3% copper
carbonate, 0.75 parts of a commercially available cellulose ether
thickener, 43.70 parts sodium tetraborate decahydrate, and 7.50
parts attapulgite clay thickener. This remedial preservative paste
contained 1.00 parts copper as derived from the fine copper
carbonate dispersion for a weight ratio of 43.7 parts boron
compound to 1.00 part copper.
Penetration testing performed on the paste composition formulated
according to the example above showed a penetration of 220 tmm.
Further, the paste composition formulated according to the above
example was brushed to 18 inches of the belowground section of 10
utility-pole sections installed in a fieldtest plot located in
Gainesville, Fla. The paste product was installed by an experienced
preservative chemical applicator and was found to have desirable
physical properties including viscosity, spreadability and
adherence for application to in-service utility poles, cross-ties
and other wooden structures.
Chemical penetration and retention was assessed at 12 months
following treatment with the paste composition formulated according
to the above example. Copper was detected at fungitoxic levels in
the outer 1/4 inch of the test poles at 12 months following
treatment. Boron was detected at levels above the fungitoxic
threshold level up to a depth of 3.0 inches from the pole surface
after 12 months. Thus desirable chemical penetration and retention
levels were obtained.
Example 10
A supplemental/remedial preservative paste composition is prepared
by blending together in the order listed; 33.66 parts water, 0.04
parts bifenthrin, 0.10 parts tebuconazole, 6.00 parts of a fine
copper dispersion comprised of 33.3% basic copper carbonate, 10.00
parts glycerin, 0.50 parts of a commercially available cellulose
ether thickener, 21.85 parts sodium tetraborate decahydrate, 21.85
parts sodium fluoride, and 6.0 parts attapulgite clay
thickener.
This remedial preservative paste contains 2.00 parts copper as
derived from the fine basic copper carbonate dispersion for a
weight ratio of 10.92 parts boron compound to 1.00 part copper and
10.92 parts fluoride compound to 1.00 part copper.
Example 11
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 44.6 parts water, 3.00
parts of a fine copper dispersion comprised of 33.3% copper
hydroxide, 0.70 parts pigmented dyes, 0.50 parts of a commercially
available cellulose ether thickener, 43.70 parts boric acid, and
7.50 parts attapulgite clay thickener. This remedial preservative
paste contained 1.0 parts copper as derived from the fine copper
hydroxide dispersion for a weight ratio of 43.7 parts boron
compound to 1.00 part copper.
Example 12
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 44.6 parts water, 3.00
parts of a fine copper dispersion comprised of 33.3% copper
hydroxide, 0.70 parts pigmented dyes, 0.50 parts of a commercially
available cellulose ether thickener, 43.70 parts sodium fluoride,
and 7.50 parts attapulgite clay thickener. This remedial
preservative paste contained 1.0 parts copper as derived from the
fine copper hydroxide dispersion for a weight ratio of 43.7 parts
fluoride compound to 1.00 part copper.
Example 13
A supplemental/remedial preservative paste composition is prepared
by blending together in the order listed; 41.79 parts water, 9.38
parts propylene glycol, 1.5 parts of a fine basic copper carbonate
dispersion comprised of 33.3% copper, 0.33 parts
didecyldimethylammonium carbonate/bicarbonate, 2.00 parts of a
commercially available cellulose ether thickener, 36.0 parts
disodium octaborate tetrahydrate, 2.0 part calcium sulfate filler
and 7.0 parts attapulgite clay thickener.
This remedial preservative paste contains 0.50 parts copper as
derived from the fine basic copper carbonate dispersion for a
weight ratio of 72.00 parts boron compound to 1.00 part copper.
Example 14
A supplemental/remedial preservative paste composition was prepared
by blending together in the order listed; 44.6 parts water, 3.00
parts of a fine copper dispersion comprised of 33.3% copper
carbonate, 0.70 parts pigmented dyes, 0.50 parts of a commercially
available cellulose ether thickener, 43.70 parts sodium tetraborate
decahydrate, and 7.50 parts attapulgite clay thickener. This
remedial preservative paste contained 1.0 parts copper as derived
from the fine copper carbonate dispersion for a weight ratio of
43.7 parts boron compound to 1.00 part copper.
A series of preservative treating formulations were prepared by
diluting the paste composition formulated according to the example
above with water. The stable dispersions were used to treat
southern pine test stakes measuring 0.75.times.0.75.times.0.75
inches by the full-cell process. Stable dispersions were prepared
to vacuum-pressure treat the test blocks rather than apply the
preservative paste to the surface of the pine test blocks, which
may have acted as a barrier or strong repellent. The treated cubes
were exposed to two common test fungi to evaluate the bio-efficacy
of the preservative formulations following procedure described in
AWPA Standard E10-12, Standard Method of Testing Wood Preservatives
by Laboratory Soil-Block Cultures. Upon completion of the
soil-block test, the cubes were found to have less than 2% weight
loss, indicating essentially no fungal attack to the treated cubes.
In comparison, untreated wood cubes had approximately 60% weight
loss after being exposed to the test fungi.
Example 15
A series of preservative treating formulations were prepared by
diluting the paste composition formulated according to Example 14
above with water. The stable dispersions were used to treat
southern pine test stakes measuring 0.75.times.0.75.times.0.75
inches by the full-cell process. Stable dispersions were prepared
to vacuum-pressure treat the test blocks rather than apply the
preservative paste to the surface of the pine test blocks, which
may have acted as a barrier or strong repellent. The treated cubes
were exposed to termites to evaluate the resistance of the
preservative formulations following the procedure described in AWPA
Standard E1-12, Standard Method for Laboratory Evaluation to
Determine Resistance to Subterranean Termites. Upon completion of
the termite test, the cubes were found to have less than 5% weight
loss with visual ratings of 8.2 to 9.4 (scale of 0 to 10, 0 being
complete failure and 10 having no attack), indicating excellent
protection against termite attack. In comparison, untreated wood
cubes had approximately 35% weight loss and a visual rating of 3.8
after being exposed to the test termites.
Example 16
A supplemental/remedial preservative paste composition was prepared
in accordance with Example 14. The paste composition was tested for
volatile organic compounds (VOC) content in accordance with EPA
Method 8620, Volatile Organic Compounds by Gas Chromatography Mass
Spectrometry (GC/MS).
Two commercially available remedial preservative paste formulations
were also tested for VOC content in accordance with EPA Method 24,
SCAQMD 304 or Modified EPA Method 8620 (which are incorporated by
reference in their entireties). The first commercially available
paste formulation, known to contain an oil-borne copper naphthenate
complex was analyzed to have a VOC content of 340 grams VOC/liter
coating. The second commercial paste product was formulated
according to U.S. Pat. No. 8,221,797, which contained a micronized
form of oxine copper that had a VOC content of 36 gramsVOC/liter
coating. Testing of a remedial preservative paste composition made
in accordance with the present invention was analyzed to have a
non-detectable level of VOCs (0.1% LOD). An oil-borne copper
naphthenate solution containing 2% copper was analyzed to have a
VOC content of 698 grams VOC/liter coating. Consequently, a
remedial preservative paste formulation that is essentially free of
volatile organic compounds was achieved.
Example 17
The supplemental/remedial preservative paste composition of Example
14 was continuously extruded through a 1/2 inch diameter aperture
and subsequently cut into 3 inch lengths. The rods were then dried
at 90.degree. F. for 24 hours. The resulting preservative rods were
found to be structurally sound, uniformly shaped and preferable for
insertion into predrilled holes such that are drilled into
in-service utility poles, piling, cross-ties and other wooden
structures for the afterprotection against wood destroying decay
fungi. Further, the rods were placed on a wet sponge partially
submerged in a water bath to allow continual wicking of water from
the bath to the rod. After six weeks it was determined through
analysis that the water bath contained appreciable levels of copper
and boron. Consequently, a preservative rod composition was
achieved.
Example 18
The supplemental/remedial preservative paste composition of Example
9 was injected into 3/8 inch holes drilled into an in-service
utility pole containing a large decay void. The preservative paste
formulation was found to be easily pumped or transferred with
standard pneumatic pumping equipment or by gravity feed. The pole
section containing the void was subsequently dissected and the
paste composition was found to have completely filled the void and
achieved intimate contact with the surfaces of the wood such that
would provide adequate diffusion of biocide to the wood substrate
in the presence of moisture or liquid water. Consequently, a
preservative internal treatment composition was achieved.
Example 19
The supplemental/remedial preservative paste composition of Example
10 was rolled onto a polyethylene sheet to a uniform thickness of
0.0625 inches. The subsequent paste/support system was cut to 21
inches in length and applied to the below ground portion of an
in-service utility pole such that the entire circumference of the
pole was incased to 18 inches below ground. As the paste/support
system was handled and transported the paste did not slump, run or
drip off of the supporting material. Removal of the paste/support
system from the pole shortly after application found that the paste
composition adhered and maintained intimate contact with to the
pole surface such that would provide adequate diffusion of the
biocide to the wood substrate in the presence of moisture or liquid
water. Consequently, a preservative wrap or bandage composition was
achieved.
Example 20
The preservative penetration and retention characteristics in
full-size southern pine pole sections initially treated with
pentachlorophenol discovered from field testing the
supplemental/remedial preservative paste composition formulated
according to Example 9 above was compared to known commercially
available paste formulations and associated third party generated
penetration and retention data.
Chemical penetration and retention was assessed at 12 months
following treatment with the paste composition formulated according
to Example 9 above. Chemical penetration and retention may be
measured by any method known in the art. Copper was detected at the
fungitoxic level of 0.04 pounds per square foot (PCF) in the outer
1/4 inch of the test poles at 12 months following treatment. The
Oregon State University--Utility Pole Research Cooperative
(OSU-UPRC) has established a threshold level for copper of 0.04 PCF
when used in remedial preservative applications (OSU-UPRC 2013
Annual Report). This value also corresponds with the copper
threshold retention level listed for copper naphthenate in AWPA Use
Category 3B (AWPA 2013 Book of Standards).
The UPRC established a field trial in November 2004 to evaluate the
performance of external supplemental preservative pastes on
southern pine utility poles initially treated with
pentachlorophenol. This study included 3 commercially available
copper containing paste formulations each of which contained copper
at 2% wt/wt that had been complexed, or solubilized with the use of
organic solvents. Copper levels for Formulation A, a fuel oil based
preservative paste that utilized an oil based naphthenic acid to
complex the copper source, were found to be 70% in excess of the
established copper threshold level of 0.04 PCF in the outer 1/4
inch of the test poles. Copper levels for Formulation B, a water
based preservative paste that utilized monoethanolamine to complex
the copper source, were found to be 168% in excess of the
established copper threshold level in the outer 1/4 inch of the
test poles. Copper levels for Formulation C, a water based
preservative paste that utilized a water dispersible naphthenic
acid to complex the copper source, were found to be 167% in excess
of the established copper threshold level 0.04 PCF in the outer 1/4
inch of the test poles. The data for Formulation C represents 2
year data as the 1 year data was unavailable.
The uncontrolled mobility of the copper component from current
paste compositions as demonstrated from the UPRC study is a concern
from a performance standpoint. Water- and oil-soluble copper
complexes provide an uncontrolled dose to the wooden structure to
be preserved that quickly disperses beyond the intended zone of
protection within the wooden structure and rapidly depletes the
copper reservoir contained within the residual paste composition
diminishing the ability of the treatment to provide prolonged
periods of protection from the action of decay and wood destroying
insects such as termites. The amount of copper that is delivered by
prior art formulations into the outer shell of the test poles is
excessive and unnecessary as levels are far in excess of fungitoxic
thresholds and a large degree of protection is also afforded by
co-biocides in each of the formulations and by any residual
chemical remaining in the poles from the initial preservative
treatment.
The slow or controlled release of the micronized copper carbonate
from the supplemental/remedial preservative paste composition made
in accordance with this invention was an unexpected and surprising
occurrence.
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